A display device includes a first substrate and a second substrate which are located opposite to each other, a liquid crystal layer located between these substrates and a seal material bonding the first substrate and the second substrate, the seal material being formed of an organic material (for example, Japanese Unexamined Patent Publication JP-A 2009-128893).
In addition, a plurality of source wirings and a plurality of gate wirings are located above a main surface of the second substrate, the source wiring and the gate wiring crossing each other. In addition, a planarization film formed of an organic material is located so as to cover the source wirings and the gate wirings. Furthermore, a display electrode is located in an area which is surrounded by the plurality of source wirings and the plurality of gate wirings on the planarization film.
Since the planarization film is located in an area of the main surface of the second substrate overlapping the first substrate, the second substrate can be planarized in the overlapped area and a distance between the first substrate and the second substrate can be uniformized when the first substrate and the second substrate are bonded to each other.
On the other hand, since the planarization film is located in the area of the main surface of the second substrate overlapping the first substrate, when the planarization film is positioned in an area of the second substrate in which the seal material is located, and the first substrate and the second substrate are bonded to each other by the seal material, the seal material is bonded to the planarization film on the second substrate.
However, since adhesiveness between the seal material and the planarization film formed of the organic material is low, the seal material is easy to be separated from the planarization film and adhesion strength between the first substrate and the second substrate may be decreased. In addition, in recent years, since the display device tends to be a thin bezel and to be increased in the size of the display screen, and an area in which the seal material is located is reduced, separation risk of the seal material by impact of dropping and stress due to twist or the like is increased.
The invention is made in view of the problems described above and an object of the invention is to provide a display device in which decreases in adhesion strength of a seal material are suppressed.